<template>
  <div id="app">
    <div class="container">
      <!-- 顶部框模块 -->
      <div class="form-group">
        <div class="input-group">
          <h4>品牌管理</h4>
        </div>
      </div>

      <!-- 数据表格 -->
      <table class="table table-bordered table-hover mt-2">
        <thead>
          <tr>
            <th>编号</th>
            <th>资产名称</th>
            <th>价格</th>
            <th>创建时间</th>
            <th>操作</th>
          </tr>
        </thead>
        <tbody>
          <tr v-for="item in list" :key="item.id">
            <td>{{ item.id }}</td>
            <td>{{ item.name }}</td>
            <!-- 如果价格超过100，就有red这个类 -->
            <td :class="{ red: item.price >= 100 }">
              {{ item.price }}
            </td>
            <!-- 方法中的函数 直接在插值语法中调用 -->
            <td>{{ formatDate(item.time) }}</td>
            <td><a href="#" @click="remove(item.id)">删除</a></td>
          </tr>
          <tr style="background-color: #eee">
            <td>统计:</td>
            <td colspan="2">总价钱为: {{ allPrice }}</td>
            <td colspan="2">平均价: {{ avgPrice }}</td>
          </tr>
        </tbody>

        <tfoot v-show="!list.length">
          <tr>
            <td colspan="5" style="text-align: center">暂无数据</td>
          </tr>
        </tfoot>
      </table>

      <!-- 添加资产 -->
      <form class="form-inline" @submit.prevent="add">
        <div class="form-group">
          <div class="input-group">
            <input
              type="text"
              class="form-control"
              placeholder="资产名称"
              v-model.trim="name"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <div class="form-group">
          <div class="input-group">
            <input
              type="text"
              class="form-control"
              placeholder="价格"
              v-model.number.trim="price"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <!-- 阻止表单提交 -->
        <button class="btn btn-primary">添加资产</button>
      </form>
    </div>
  </div>
</template>

<script>
import moment from 'moment'
import 'bootstrap/dist/css/bootstrap.css' // 默认找文件夹下的index文件(但是这个不是所以需要写路径)
import { nanoid } from 'nanoid'
export default {
  data() {
    return {
      name: '', // 名称
      price: '', // 价格
      // list: JSON.parse(localStorage.getItem('list') || '[]')
      list: JSON.parse(localStorage.getItem('pList')) || []
    }
  },
  methods: {
    add() {
      if (!this.name || (!this.price && this.price > 0))
        return alert('请输入内容!')
      const i = {
        id: nanoid().slice(0, 7),
        name: this.name,
        price: this.price,
        time: new Date()
      }
      this.list.push(i)
      this.name = ''
      this.price = ''
    },
    remove(id) {
      this.list = this.list.filter((item) => {
        return item.id !== id
      })
    },
    formatDate(date) {
      return moment(date).format('YYYY-MM-DD')
    }
  },
  computed: {
    allPrice() {
      return this.list.reduce((sum, item) => {
        return (sum += item.price)
      }, 0)
    },
    avgPrice() {
      return (this.allPrice / this.list.length || 0).toFixed(2)
    }
  },
  watch: {
    list: {
      deep: true,
      handler() {
        // localStorage.setItem('list', JSON.stringify(newVal))
        localStorage.setItem('pList', JSON.stringify(this.list))
      }
    }
  }
}
</script>

<style>
.red {
  color: red;
}
</style>
